Hello guys
I have a tube pre witch is i think an mu stage cathode follower. It uses 1 x 12au7 and 1x 12at7 each channel. Its a complete dual mono design with 2 independent PSU in a separate box. In the psu for EACH CHANNEL we have 2 separate toroidal one for high voltages and one for the low voltages. The voltages are a b+ 217v at 120 mA , a 12v at 1A all DC regulated and 6.3v AC. The b+ is regulated by an ECL82 tube thats why we have the 6.3v ac for the heaters of ECL82 to operate.
My question is...
At the b+ we have 4 diodes IN4007 and then the ecl82 for regulation with the caps resistors an all the needed parts for the application.
At the filaments section we have 4 diodes IN4004 then a 7812 regulator and all again the needed parts as above. The filaments are in series 12v dc
The 6.3 is ac direct to the ECL82
Can i safely replace all the 8 diodes in each channel psu with the VISAY uf4007 or i am going to start a nuclear disaster 💣here?
I have a tube pre witch is i think an mu stage cathode follower. It uses 1 x 12au7 and 1x 12at7 each channel. Its a complete dual mono design with 2 independent PSU in a separate box. In the psu for EACH CHANNEL we have 2 separate toroidal one for high voltages and one for the low voltages. The voltages are a b+ 217v at 120 mA , a 12v at 1A all DC regulated and 6.3v AC. The b+ is regulated by an ECL82 tube thats why we have the 6.3v ac for the heaters of ECL82 to operate.
My question is...
At the b+ we have 4 diodes IN4007 and then the ecl82 for regulation with the caps resistors an all the needed parts for the application.
At the filaments section we have 4 diodes IN4004 then a 7812 regulator and all again the needed parts as above. The filaments are in series 12v dc
The 6.3 is ac direct to the ECL82
Can i safely replace all the 8 diodes in each channel psu with the VISAY uf4007 or i am going to start a nuclear disaster 💣here?
Last edited:
The difference between the 1N4004 and 1N4007 diodes is the reverse voltage rating. They both have the same 1 amp current rating.
The 1N4004 is rated at 400 peak inverse volts and the 1N4007 is rated at 1000 volts. So you can safely replace a 1N4004 with a 1N4007 but not vice versa. The short answer to your question is "yes."
The 1N4004 is rated at 400 peak inverse volts and the 1N4007 is rated at 1000 volts. So you can safely replace a 1N4004 with a 1N4007 but not vice versa. The short answer to your question is "yes."
That seems ok, but exercise extreme caution due to the high DC and AC voltages present in the circuitry.
I would test the new filament circuits first, before changing the HV diodes.
I would test the new filament circuits first, before changing the HV diodes.
The diodes are completely interchangeable so long as you don't exceed the PIV (peak inverse voltage) rating of whichever diode you use.
Thanks guys for your fast responses.
I want to change them because there were not new when i installed them. I took them from an old 30 years tube amp and i want to try the faster uf version
I want to change them because there were not new when i installed them. I took them from an old 30 years tube amp and i want to try the faster uf version
Yes you are wright mate safety comes first. I learned this the hard way too many times.